Switch devices are generally used to selectively couple two terminals of the switch device electrically with each other, e.g. to thereby couple for example two parts of an electronic circuit. A particular kind of switch devices are power switch devices, which serve to selectively couple a load to a supply voltage like a positive supply voltage, a negative supply voltage or ground.
In electronic circuits, in many cases transistors are used as switch devices, for example field effect transistors (FETs) like metal oxide semiconductor field effect transistors (MOSFETs), bipolar transistors or insulated gate bipolar transistors (IGBTs). In some applications, such switch devices have to operate over a wide temperature range. For example, IGBT modules in automotive applications like electric vehicles or traction control application have to operate over a wide temperature range, for example from about −55° C. or −40° C. up to 125° C. or even 175° C.
Bipolar semiconductor devices like IGBTs, bipolar transistors or diodes change their switching behavior with temperature. In particular, a carrier lifetime in such devices has a positive temperature coefficient. This e.g. causes a switch-off speed dI/dt (derivative of current I with respect to time t) to become faster (i.e. greater absolute value of dI/dt) with lower temperatures. A fast switching in turn may cause voltage peaks when switching the switch device.
Furthermore, a blocking behavior of the semiconductor devices decreases with decreasing temperature, i.e. breakthrough or other events which cause switch device to conduct current may occur at lower voltages for lower temperatures than for higher temperatures.
In conventional solutions, to avoid or mitigate voltage peaks, switching on and off the switch device is performed slowly enough to keep such voltage peaks within a tolerable range. To achieve this resistors have been coupled to control terminals (for example gate terminals) of switch devices. However, these resistors were designed for a worst case, for example lowest temperature of a specified operating range, which led to comparatively high resistors associated with corresponding high power dissipation of the switch device in particular at higher operating temperatures.